PURE DATA forum~

Are there restriction to the amount of osc~?

Hey drnn, I believe it's just one [osc~] only.

oops, sorry about that.  no-one had permission to read or write attachments.  :D

should be fine now.

read and write away!

(oh, and yeah,...there are some 'rules' for this challenge thing...but yeah...i'm not going to go deleting your post if you bend them a little bit.)

juste-osc-1.pd , making sawtooths using [osc~] !!!

love the [dbtorms] as scaling device.

here's a little lazer fx patch based on that.

but [bang~] is technically another signal object ;)

you did good.

I was thinking of this, too. I really wanted to use [block~ 1] so I could cheat and just use [osc~] as a table-lookup using the phase inlet (though I haven't actually checked to see if it has that 64-sample limit that objects like [bang~] do).

extremely lo-fi "sampler" of sorts.  extracts basic pitch and amplitude information from a soundfile and plays it back one block at a time using [osc~]

by switching the sine wave on and then off again, it is possible to make a filter/formant type of effect (there are examples of this in the pd docs, using a different technique)

here's a simple one, and then the same thing with some sequencing

resetting the [osc~] phase introduces a discontinuity in the signal.  The waveform suddenly jumps from whatever value it was at, to the value forced upon it by the reset.  These sudden jumps in waveform introduce a lot of harmonics to the sound, generally resulting in a 'buzzy' sound. 

This is why a sine wave sounds very clean and round, but a sawtooth wave sounds fuzzy and noisy. 

If you look at matju's sawtooth patch, it uses the same principle.  (as do parts of maelstorm's one)

While making the sawtooth patch, I started wondering about ways to construct the best possible approximation to a sound using only one sine wave per block (and not necessarily a whole number of cycles). This means picking the best matching frequency and phase for each block. That's somewhat hard to solve, and it depends on the criterion of similarity being used. But I wonder what it would sound like.

BTW, much of the brrrrrr anomaly that appears in the sawtooth is because there are a variable number of blocks per cycle. E.g. if a cycle should last 23.25 blocks, then the cycles will have durations 23, 23, 23, 24, 23, 23, 23, 24, ... which gives a strange and very fast vibrato. Using a ideal approximator, you could get something that sounds much smoother (that is, in which the distorsions are still very present but not rough).

matju wrote:

I started wondering about ways to construct the best possible approximation to a sound using only one sine wave per block (and not necessarily a whole number of cycles). This means picking the best matching frequency and phase for each block. That's somewhat hard to solve, and it depends on the criterion of similarity being used. But I wonder what it would sound like.

that's pretty much the approach i took with the 'sampler' i did. 

i had to hack it pretty badly though, because once the osc~ frequency gets to 1/4 of block size, there is no longer any way to control amplitude - which from my observations, seems to be more important than pitch in making a sample play back with some degree of recognisability.  My hack was just to scale the pitch by the amplitude.  Somehow it works - at least for really simple sounds where pitch doesn't matter too much and rhythm is more pronounced.  So, i could make drum loops play back and still sound quite like drumloops.


by the way,
i've never seen that [f ]x[+ 1]x[& 255] structure before.  that's really cool.